It is common knowledge that cheats exist in PC games. Most game developers try to protect their games with anti-cheat or guardian software to eradicate cheats and hacks. However, not every system is perfect, even in established games like Dota 2 on Steam.
Known cheats in Dota are often scripts, auto-casts, and auto-combo. The more blatant cheat in Dota 2 is map hacking, gaining the vision even in the fog of war. The most abusive heroes with these kinds of cheating are Skywraith Mage, Arc Warden, Techies, Invoker, and Meepo.
Cheating online in casual matches is a pain for players. It is often hard to detect and ban all those cheaters from the server. It is often a hard task to go through all the replays to actually frame one player as a cheater and the punishment is often simply getting VAC-ed (Valve Anti Cheat) and banned from the game.
Cheats, in general, are often used by low-skill players in pubs just to gain better advantages in the game. They are often defeated by teamwork and cause nothing serious outside of the game. However, cheating to win something competitively is something entirely different.
Recently, one player posted a thread on Reddit to allege that he faced against a cheater in a $15,000 tournament. That is big prize money intended as incentives to promote Dota 2 in some regions. More specifically, it was Dom.ru Championship 2019 played online with the 1st place team scooping $7,786.
It was right in this tournament that a user named Bomber_MoreMMR on Reddit stated that the CIS player Broxy was the main suspect. Broxy was once banned for cheating on the Tinkoff Dota Cup, but still managed to play in the Dom.ru Championship 2019 tournament and got away with first place victory.
In the recent tournament, there were many situations where the suspect showed some signs of cheating, most probably a map hack, gaining knowledge of warding spots. The Reddit user uploaded one video showing the game and the situation.
Most of the case was questionable with Broxy's decision to act against the common logic.
The more unintelligible situation was with Nyx and Sand King when they played hide and seek in the bush where SK clearly could not "hide" from Broxy.
Also, there is more evidence of the obvious cheating of the mentioned player. At the moment, the Reddit thread was marked as unconfirmed. It is still up for debate as the suspect has yet to comment anything regarding the issue.